An example of prior art boxing system is shown in Japanese Unexamined Patent Publication (KOKAI) No. HEI 9-77003 published on Mar. 25, 1997. This prior art boxing system is used to put packs 1 shown, for example, in FIG. 25(a) or boxes (not shown) in a case 2 shown, for example, in FIG. 25(c). Referring to FIG. 25(a), packs 1 conveyed on an input conveyor 4 are put into spaces 6 formed between a plurality of adjacent ones of a plurality of fins 5 planted on the conveying surface of an alignment conveyor 3. One pack is put into one space 6. Thus, packs 1 are aligned on the conveying surface of the alignment conveyor 3, standing erect.
When a predetermined number, five in the illustrated example, of packs 1 are aligned on the conveyor 3, a pusher plate 11 pushes five packs on the conveyor 3 to move on a U-shaped intermediate member 10 onto a predetermined position on gates 7-1 and 7-2 as shown in FIG. 25(b). The pusher plate 11 has slits 12 therein to avoid interference with the fins 5 when it pushes five packs on the alignment conveyor 3. In the illustrated example, two sets of five packs 1 have been pushed onto the gates 7-1 and 7-2.
As shown in FIGS. 25(c) and 25(d), after pushing five packs 1 onto the predetermined position on the closed gates 7-1 and 7-2, the pusher plate 11 moves upward and returns to its original standby position (FIG. 25(a)) along a path above the alignment conveyor 3 in order to avoid interference with succeeding packs 1 being conveyed and aligned on the conveyor 3.
Then, as shown in FIG. 25(b), the packs 1 standing erect on the gates 7-1 and 7-2 are held by a pair of holding plates 9-1 and 9-2.
Thereafter, as shown in FIG. 25(c), the gates 7-1 and 7-2 are opened, and the cardboard case 2 is moved upward from below the gates 7-1 and 7-2 so that the ten packs 1 held between the holding plates 9-1 and 9-2 are put into the cardboard case 2. The cardboard case 2 has been conveyed on a roller conveyor (not shown) to a predetermined position below the gates 7-1 and 7-2. The cardboard case 2 has four flaps 2a-2d.
Next, a stuffing plate 13 disposed above the gates 7-1 and 7-2 is lowered, and, at the same time, the holding plates 9-1 and 9-2 are moved in the direction away from each other. In this manner, packs 1 are placed in the cardboard case 2, as shown in FIG. 25(c).
Then, the cardboard case 2 with packs 1 put therein is lowered, and the gates 7-1 and 7-2 are closed, so that the boxing system returns to the state shown in FIG. 25(a) to thereby complete one cycle of operation. This operation is repeated.
In the above-described prior art boxing system, the alignment conveyor 3 must be stopped at the pushing position shown in FIG. 25(a) when the pusher plate 11 pushes five packs 1 on the alignment conveyor 3 onto the intermediate member 10. It disadvantageously prevents packs 1 conveyed by the input conveyor 4 from being continuously supplied onto the alignment conveyor 3. Another problem is as follows. When one set of five packs 1 is pushed off the alignment conveyor 3, a next set of five packs 1 may have been already available. However, such new set cannot be brought to the pushing position at a high speed, since the alignment conveyor 3 should move at a speed low enough to receive packs 1 supplied by the input conveyor 4 without fail. These problems impede the improvement of the boxing efficiency of prior art systems.
For conveying and boxing thick packs in a case, the spacing between adjacent fins 5 should be increased. The fins 5 are screwed to the conveying surface of the conveyor 3. In order to widen the spaces 6, the fins 5 must be unscrewed, which requires time and labor.
As shown in FIG. 25(a), the holding plates 9-1 and 9-2 are arranged to advance by a predetermined stroke to press against a given number of packs 1 between them. Accordingly, if each of the five aligned packs 1 to be held is relatively thick, there is a danger that the holding plates 9-1 and 9-2 may crush items contained in the packs 1. On the other hand, if the sum thickness of the five packs 1 is relatively small, they may slip off from between the holding plates 9-1 and 9-2. Accordingly, a predetermined number of packs 1 may not be boxed neatly. Thus, it is not always possible for the holding plates 9-1 and 9-2 of the prior art system to hold different sized packs with force appropriate for such packs.
Further, since the holding plates 9-1 and 9-2 hold packs 1 by applying holding forces along the line on which packs 1 are aligned in a row, all or some of aligned packs 1 may slip out from the row in the lateral direction. Such packs 1 may be caught by the upper edge of a side-wall of the case 2, and, therefore, sometimes, proper boxing of packs 1 cannot be done.
Sometimes, a large number of packs 1 may be in so long a row, being held between the holding plates 9-1 and 9-2, that one or more of packs 1 may slip off. If the force given by the holding plates 9-1 and 9-2 to the row of packs 1 is increased to prevent such slip-off of packs, the packs may be sometimes damaged. Accordingly, there is some limit on the holding force applied by the plates 9-1 and 9-2.
In prior art systems, in order for packs 1 to be put into a case easily, the case should have a relatively large opening, which means that large-sized cases 2 are required. This necessitates a relatively large space for storing the packed cases 2.
An object of the present invention is to provide a boxing system in which a desired number of packs can be put into cases at a high rate without fail.
Another object of the present invention is to provide a conveyor apparatus which can be used in the boxing system and which includes a plurality of easily detachable fins, between adjacent ones of which packs conveyed to be put into a case are disposed and supported.
Still another object of the invention is to provide such fins between adjacent ones of which packs can be supported, standing erect without bend, so that the packs can be put into cases, being erected.